The 1, 3-enyne moiety is an important structural unit for biologically active and natural compounds.
2.
*Enyne cyclization, in particular cycloisomerization, one early example being an 5-exo-dig 1, 6 enyne cycloisomerization:
3.
*Enyne cyclization, in particular cycloisomerization, one early example being an 5-exo-dig 1, 6 enyne cycloisomerization:
4.
Many metabolites found in nature contain alkyne or enyne moieties, and therefore, the Sonogashira reaction has found frequent utility in their syntheses.
5.
There is not a single mechanism that can be used to describe enyne cycloisomerizations as the mechanism depends on reaction conditions and catalyst selection.
6.
A versatile function of Au ( I ) catalyzed enyne cycloisomerization is the construction of asymmetric medium sized rings, which is a challenge in the synthesis of ornamented molecular design.
7.
Notably, in this example chirality transfer takes place in which the absolute stereochemistry of the enyne ( "'26 "') controls stereochemistry of the product ( "'27 "').
8.
An example of a 1, 6 enyne cycloisomerization proceeding through an ? 2 activated metal intermediate is given in figure 8, which is common for enyne cycloisomerizations mediated by Pt or Au due to their ? acidic nature.
9.
An example of a 1, 6 enyne cycloisomerization proceeding through an ? 2 activated metal intermediate is given in figure 8, which is common for enyne cycloisomerizations mediated by Pt or Au due to their ? acidic nature.
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